[coreboot] SerialICE - Qemu based x86 firmware debugger

Stefan Reinauer stepan at coresystems.de
Thu Oct 29 12:59:55 CET 2009

Dear x86 hardware and low-level software developers and enthusiasts!

coresystems GmbH is glad to release a new version of our "Integrated
Circuit Emulator over Serial", short SerialICE.

Short description:

SerialICE (http://www.serialice.com) is a BIOS/Firmware debugging tool.
It allows you to run and observe BIOS images (such as coreboot®:
http://www.coreboot.org/) written for real hardware in Qemu
(http://www.qemu.org) for debugging purposes. Thanks to Qemu's
compelling feature set, it's also possible to debug this BIOS code with

SerialICE consists of three parts:

- a serial console "rom shell" compiled with romcc, with minimal footprint.
- a patch to Qemu 0.11.0, which adds a new "SerialICE" machine.
- a LUA script that contains filters, loggers and other SerialICE
specific configuration and adaption

SerialICE can be downloaded from http://www.serialice.com/.

With "qemu -m serialice -serialice /dev/ttyS0 -L
path-to-your-bios.bin-dir -hda /dev/zero" you can run an arbitrary BIOS
binary written for your target hardware in Qemu, thus logging all IO and
memory accesses. Those operations will additionally be transmitted to
the target system's shell and are executed there, while their results
are submitted back to Qemu.

Operations sent to the target:
- memory reads/writes (some of them)
- IO reads/writes
- MSR reads/writes
- CPUID calls (the bios code path might rely on this)

Note: The code is still quite experimental and only supports a few
number of mainboard out of the box, but it was already useful in some
debugging scenarios we had and was able to reveil information that would
normally only be available with a hardware debugger of the price of a
new car. Don't expect SerialICE to completely replace a ICE/JTAG/ITP
device, but it might just work for your case, as it did for us.

The ROM code needs minimal board/chipset specific setup in order to
establish serial communication with Qemu. See mainboard/* for a few
examples.  This release contains setup code for 7 mainboards.
Also, some hardware accesses have to be caught in the LUA code
(scripts/serialice.lua) in order to prevent the system from locking up
(ie. when the BIOS is disabling the serial console).

Among the new features:
 - Completely scriptable filtering and logging with LUA and bitlib.
 - Kconfig/Kbuild support (make menuconfig)
 - New mainboards supported: Intel D945GCLF, ASUS M2V-MX SE, MSI MS6178,
Thomson IP1000, Dell PowerEdge s1850, RCA RM4100
 - Patch against latest Qemu version 0.11.0.
 - Support for compiling with XMMSTACK and ROMCC.
 - Many bugs fixed: serial communication, data corruption by
signed/unsigned casts, ...

Known issues:
- microcode updates from within emulated ROM code will fail.
- some rarely used calls of cpuid and rdmsr/wrmsr might not give the
correct information

Special thanks go to Daniel Liu, Rudolf Marek, Ron Minnich, Joe Smith,
Uwe Hermann and Mark Marshall for their bug fixes and contributions to
this release.

See http://www.serialice.com/ for more information.

Comments and patches are of course very welcome!

Best regards,

Stefan Reinauer

coresystems GmbH • Brahmsstr. 16 • D-79104 Freiburg i. Br.
      Tel.: +49 761 7668825 • Fax: +49 761 7664613
Email: info at coresystems.dehttp://www.coresystems.de/
Registergericht: Amtsgericht Freiburg • HRB 7656
Geschäftsführer: Stefan Reinauer • Ust-IdNr.: DE245674866

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